Why does an error occur when trying to change the table encoding?

Question

MySQL

There is a WordPress database, the tables of which have a different encoding - utf8mb4_unicode_520_ci, utf8_general_ci, utf8mb4_general_ci
I want to convert everything at once to utf8_general_ci
I make a request:

ALTER TABLE `schools`.`wp_10_ap_activity` CONVERT TO CHARACTER SET utf8_general_ci COLLATE utf8mb4_unicode_520_ci;
ALTER TABLE `schools`.`wp_10_commentmeta` CONVERT TO CHARACTER SET utf8_general_ci COLLATE utf8mb4_unicode_520_ci;
....

But there is an error #1115 - Unknown encoding 'utf8_general_ci'
MySQL Version 5.6

Answer 1

utf8mb4 is wider than just utf8
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